Synthesis And Properties Of Organic Silicone Modified Polyurethane Acrylate Waterborne Prepolymer

Water-borne UV curable system solves the environmental problems that are caused by the volatile organic compounds and has the advantages of UV curable technology,which is environmentally friendly and has become one of the main development directions of UV coatings.The water-borne prepolymers are a key component that determines the main properties of UV water-borne materials,therefore,the design and development of water-borne prepolymers with novel structures and excellent properties have important theoretical significance and application value.The combination of organosilicone and polyurethane acrylate can enhance the surface properties(decreasing surface energy,improving the water resistance),heat resistant properties and tensile properties of the UV-cured materials.In addition,the rigid ring structure has a remarkable effect on the hardness,gloss,tensile properties,and adhesion forces of the UV-cured materials.Based on these reasons,this work has designed and synthesized organosilicone-modified polyurethane acrylate water-borne prepolymers with novel structure and excellent comprehensive performances.Moreover,Fe3O4 nanoparticles have high saturation magnetization and mechanical properties,which can improve the heat resistance and mechanical properties of the materials,and endow hybrid materials with the magnetic and electrical properties.On this basis,this work has studied the properties of organic-inorganic hybrid materials composing of modified Fe3O4 nanoparticles and water-borne prepolymers.This work will enrich the basic theoretical research of water-borne UV-cured materials and broaden its application field.The main research contents and conclusions are as follows:1.A novel small molecular chain extender containing rigid ring,isobornyl 3-(bis(2-hydroxyethyl)amino)propanoate(DEAIBOA),and twelve kinds of organosilicone-modified polyurethane acrylate water-borne prepolymers were synthesized based on polyethylene glycol(PEG),3-isocy anatomethy 1-3,5.5-trimethy lcyclohexyl isocyanate(IPDI),diethanolamine(DEOA),triethylamine(TEA),isobornyl acrylate(IBOA),pentaerythritol triacrylate(PET3A),2,2-dimethylol propionic acid(DMPA)and 2-hydroxyethyl acrylate(HEA),and their structures were determined.2.The photopolymerization properties,water solubility,and the emulsions stability and particle size of the twelve kinds of organosilicone-modified polyurethane acrylate water-borne prepolymers were investigated.The results show that these prepolymers have good water solubility and photopolymerization properties,and their emulsions possess good storage stability.With the increase of the hydrophilic capability,the emulsion particle size decreased,on the contrary,with the increase of molecular weight,the emulsion particle size increased.3.The properties of the UV-cured films of seven kinds of water-borne prepolymers with different hydrophilicity(different DMPA contents)and different functionalities were investigated.The results show that all UV-cured films have good yellowing resistance.With the increase of DMPA content of water-borne prepolymers,the tensile strength enhanced,the elongation at break decreased.Increasing the functionality of the prepolymers can increase the gel rate,heat resistance,tensile strength and pencil hardness of the UV-cured films.4.The properties of the UV-cured films of five kinds of water-borne prepolymers with different rigid rings contents were investigated.The results show that the tensile strength,glass transition temperature and pencil hardness of the UV-cured films increased with the increase of the content of the rigid ring in the prepolymers.The elongation at break of the cured films increased initially but then decreased.Compared with the UV-cured films without rigid ring structure,the tensile strength,the elongation at break and the adhesion force of the UV-cured film with rigid ring structure were increased.5.The structure of Fe3O4@SiO2@IPDI-HEA was determined.The photopolymerization property of Fe3O4@SiO2@IPDI-HEA and the properties of the UV curable systems with different Fe3O4@SiO2@IPDI?HEA contents were investigated.The results show that the particle size distribution of Fe3O4@SiO2@IPDI-HEA was uniform and the particle size was 90 nm.The water-borne UV curable systems with different Fe3O4@SiO2@IPDI-HEA contents had good photopolymerization properties,but the polymerization rates were obviously lower than those of the water-borne UV curable systems without Fe3O4@SiO2@IPDI-HEA.With the increase of Fe3O4@SiO2@IPDI-HEA content,the heat resistance was improved and the elongation at break of the UV-cured films decreased,while the tensile strength of the cured films increased initially but decreased later.The dielectric constant and the dielectric loss increased with the increase of Fe3O4@SiO2@IPDI-HEA content,hence,Fe3O4@SiO2@IPDI-HEA may have a certain application prospect in water-borne UV-curale radio wave absorbing materials.